As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE REMOVED DUE TO CRACKED EXHAUST COLLECTOR. COMPRESSOR REPAIRED DUE TO WHINE BETWEEN 10 PERCENT AND 35 PERCENT TORQUE. INSPECTION OF COMPRESSOR PARTS REVEALED SPUR GEAR SHAFT AFT SPLINES FAILED NO-GO GAUGE CHECK. INSTALLED A NEW SPUR GEAR SHAFT.